The present invention relates generally to the art of seating and more particularly to an upper back support in a seat.
A wide variety of comfort controlled vehicle seating systems are well-known and currently in use. Simple systems provide fore and aft adjustability and reclining of the seat back. More sophisticated seating systems add manual or power lumbar supports, vertically adjustable headrests, height and tilt controls for the seat cushion, and the like. Many of the current seats are designed and modeled for a mannequin named xe2x80x9cOSCARxe2x80x9d in the industry and more specifically to the movement of OSCAR about a hip joint center.
Researchers at Michigan State University in the early 1990""s began to look more carefully at actual movements of the body in an automotive vehicle setting and came up with a new modelxe2x80x94xe2x80x9cJOHNxe2x80x9d named after the research sponsor, Johnson Controls, Inc.xe2x80x94and developed relationships between thorax and pelvic movement and the impact on lumbar curvature.
These researchers determined that there is a relationship between these two movements and that a desired curvature for the lumbar area could be created if the thorax area is moved significantly. Instead of having a lumbar support push the lumbar vertebrae forwardly (mechanical, pneumatic, manual, powered, etc.), they found that the thorax area moves in a counter rotation with respect to the pelvis. When the thorax moves forward in this model, the shoulders actually move rearwardly. This work led to the prediction that seat comfort could be enhanced if the thorax could be supported in all positions from the equivalent of JOHN being slumped forwardly on a stool to a position in which JOHN is sitting erect, with a total lumbar curvature of about 50xc2x0.
Despite this theoretical explanation of seating comfort, developments in the 1990""s continued to focus on lumbar support and lumbar height, and several vehicles currently being sold include lumbar supports that go up and down as well as in and out. While seeming to provide some comfort enhancement for vehicle seating occupants, such products ignore the research findings that comfort can, in fact, be enhanced if thorax support is also provided.
As background, it is well recognized that static seats or those employing baskets, paddles and bladder systems can be used for lumbar support. The latter are all variations on a single principle. Each forces the lumbar region into a lordotic or concave shape with the intent of creating a more erect posture and hence greater comfort. Lumbar paddles and baskets can be manually operated or powered. Lumbar bladders are filled with air using a manual pump or an electrically powered pump to increase the bladder""s volume and the amount of prominence into the back.
Two additional static seats which discuss comfort are known to the present inventors. A so-called xe2x80x9ciliacxe2x80x9d seat has a contour in the pelvic region and an extreme amount of contour in the location of the iliac crests of the pelvis. Their purpose is to support the pelvis and avoid hyperflexion of the lower lumbar joints to eliminate the probability of pain. The second is called a New Generation Ergonomic Seat which features a lumbar support and a seat contour which is designed to provide support from the pelvis (sacrum) to the 10th thoracic vertebrae (located at the bottom of the thorax). This seat simulates a position the body would assume if lying in a bed, a so-called xe2x80x9cneutralxe2x80x9d position with less curvature than would be encountered if the person was standing erect.
Yet a further seat maneuvering system includes a cushion, a lower back support and an upper back support, the latter two being pivotally coupled in the mid-back region. The cushion moves on a pair of rollers in an arc relationship to the mid-back pivot. While the main object of the seat is safety (i.e., anti-submarining), increased comfort is attributed to the seat by the inventor.
Another seat has pelvis, lumbar and thoracic support, but movement of them is controlled solely by movement of the lumbar support. The other two are connected to it, the thoracic support being pivotally connected to the top of the seat back frame. This allows the shoulders to recline and the lower part of the thorax to be supported.
A biomechanically articulating chair has been devised and was built around the movements of the xe2x80x9c2D JOHNxe2x80x9d model. Allegedly it provides improved postural support by supporting the pelvis, thorax, and the lumbar region. The seat articulates as if xe2x80x9cJOHNxe2x80x9d pivots on the ischial tuberosites. The pelvis support pivots just under the ischial tuberosites of the occupant, while the thorax support pivots in the mid-back. The chair is intended to support the occupant through a wide range of spinal curvature and torso recline angles, thereby maintaining geometric compatibility between the height of the occupant and the seat contour to eliminate undesirable pressure distributions on the occupant. This chair is known for use in the office furniture or home fields and is not specifically illustrated for use with motor vehicle seating.
While several of the above-mentioned seat constructions can enhance occupant comfort, the present inventors believe a substantial improvement over all of them can be provided. Such improvement would be considered an important advance in this art.
A primary feature of the present invention is to overcome the above-noted disadvantages of prior art seating systems by providing a seat that more closely follows the way a seated person moves and uniformly supports the upper back or thorax, thus providing a wider range of seated positions that are available in any currently known seating.
The present invention provides a seat comprising a base assembly including a seat support. A seat member is supported on the base assembly with a back frame pivoted to the base assembly or any suitable mounting structure within the seat assembly for movement. A back shell is connected to the back frame and an upper back support is coupled to the back shell. The upper back support comprises a panel having a lower portion and an upper portion, with the lower portion flexibly coupled to the back shell of the seat. A resilient member is coupled to the panel proximate the upper portion and to the back shell of the seat. Additional resilient members can be coupled to the panel in a spaced apart relationship to the other resilient member. Another embodiment of the seat includes a headrest coupled to the upper portion of the panel and a support frame assembly coupled to the headrest and the back frame of the seat.
The present invention also provides an upper back support in a vehicle seat, with the vehicle seat having a base assembly including a seat support. The seat member is supported on the base assembly and a back frame is pivoted to the base assembly or any suitable mounting structure within the seat assembly for movement. A back shell is connected to the back frame and an upper back support is coupled to the back shell. The upper back support comprises a panel having a lower portion and an upper portion, with the lower portion flexibly coupled to the back shell of the vehicle seat. A resilient member is coupled to the panel proximate the upper portion and to the back shell of the vehicle seat. An additional resilient member can be coupled to the panel proximate the upper portion and to the back shell of the vehicle seat in a spaced apart relationship to the other resilient member. Another embodiment of the upper back support includes a headrest coupled to the upper portion of the panel and a support frame assembly coupled to the headrest and the back frame of the vehicle seat.
The present invention further provides an upper back support for an occupant of the seat with the seat having a base assembly including a seat support and a seat member supported on the base assembly. A back frame is pivoted to the base assembly or any suitable mounting structure within the seat assembly for movement and a back shell is connected to the back frame. The upper back support comprises a means for supporting having a lower portion and an upper portion, a means for coupling attached to the lower portion of the means for supporting and attaching to the back shell of the seat. A means for biasing is coupled to the means for supporting proximate the upper portion and to the back shell of the seat. Another embodiment of the upper back support includes a means for resting the head of the occupant coupled to the upper portion of the means for supporting and a means for holding coupled to the means for resting and the back frame of the vehicle seat.
The present invention further provides a method of assembly of a seat having an upper back support, with the seat having a base assembly including a seat support and a seat member supported on the base assembly. A back frame pivoted to the base assembly or any suitable mounting structure within the seat assembly for movement and a back shell connected to the back frame with an upper back support flexibly coupled to the back shell. The method comprises the steps of providing a panel having a lower portion and an upper portion and providing a flexible coupler having a first end and a second end. Then attaching the first end of the flexible coupler to the lower portion of the panel and attaching the second end of the flexible coupler to the back shell. Then providing a resilient member having a first end and a second end and inserting the resilient member between the panel and the back shell. Attaching the first end of the resilient member to the panel proximate the upper portion of the panel and attaching the second end of the resilient member to the back shell. Another embodiment of the method includes the step of providing a second resilient member having a first end and a second end and inserting the second resilient member between the panel and the back shell in a spaced apart relationship from the other resilient member and attaching the first end of the second resilient member to the panel proximate the upper portion of the panel and attaching the second end of the second resilient member to the back shell. Another embodiment of the method includes the steps of providing a headrest and attaching the headrest to the panel. It also includes providing a support frame assembly and attaching the support frame assembly to the back frame of the seat and aligning the assembly with the headrest.